tests/test-paths.t

ui: support declaring path push urls as sub-options

Power users often want to apply per-path configuration options. For
example, they may want to declare an alternate URL for push operations
or declare a revset of revisions to push when `hg push` is used
(as opposed to attempting to push all revisions by default).

This patch establishes the use of sub-options (config options with
":" in the name) to declare additional behavior for paths.

New sub-options are declared by using the new ``@ui.pathsuboption``
decorator. This decorator serves multiple purposes:

* Declaring which sub-options are registered
* Declaring how a sub-option maps to an attribute on ``path``
  instances (this is needed to `hg paths` can render sub-options
  and values properly)
* Validation and normalization of config options to attribute
  values
* Allows extensions to declare new sub-options without monkeypatching
* Allows extensions to overwrite built-in behavior for sub-option
  handling

As convenient as the new option registration decorator is, extensions
(and even core functionality) may still need an additional hook point
to perform finalization of path instances. For example, they may wish
to validate that multiple options/attributes aren't conflicting with
each other. This hook point could be added later, if needed.

To prove this new functionality works, we implement the "pushurl"
path sub-option. This option declares the URL that `hg push` should
use by default.

We require that "pushurl" is an actual URL. This requirement might be
controversial and could be dropped if there is opposition. However,
objectors should read the complicated code in ui.path.__init__ and
commands.push for resolving non-URL values before making a judgement.

We also don't allow #fragment in the URLs. I intend to introduce a
":pushrev" (or similar) option to define a revset to control which
revisions are pushed when "-r <rev>" isn't passed into `hg push`.
This is much more powerful than #fragment and I don't think #fragment
is useful enough to continue supporting.

The [paths] section of the "config" help page has been updated
significantly. `hg paths` has been taught to display path sub-options.

The docs mention that "default-push" is now deprecated. However, there
are several references to it that need to be cleaned up. A large part
of this is converting more consumers to the new paths API. This will
happen naturally as more path sub-options are added and more and more
components need to access them.

  $ hg init a
  $ hg clone a b
  updating to branch default
  0 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ cd a
  $ echo '[paths]' >> .hg/hgrc
  $ echo 'dupe = ../b' >> .hg/hgrc
  $ echo 'expand = $SOMETHING/bar' >> .hg/hgrc
  $ hg in dupe
  comparing with $TESTTMP/b (glob)
  no changes found
  [1]
  $ cd ..
  $ hg -R a in dupe
  comparing with $TESTTMP/b (glob)
  no changes found
  [1]
  $ cd a
  $ hg paths
  dupe = $TESTTMP/b (glob)
  expand = $TESTTMP/a/$SOMETHING/bar (glob)
  $ SOMETHING=foo hg paths
  dupe = $TESTTMP/b (glob)
  expand = $TESTTMP/a/foo/bar (glob)
#if msys
  $ SOMETHING=//foo hg paths
  dupe = $TESTTMP/b (glob)
  expand = /foo/bar
#else
  $ SOMETHING=/foo hg paths
  dupe = $TESTTMP/b (glob)
  expand = /foo/bar
#endif
  $ hg paths -q
  dupe
  expand
  $ hg paths dupe
  $TESTTMP/b (glob)
  $ hg paths -q dupe
  $ hg paths unknown
  not found!
  [1]
  $ hg paths -q unknown
  [1]
  $ cd ..

sub-options for an undeclared path are ignored

  $ hg init suboptions
  $ cd suboptions

  $ cat > .hg/hgrc << EOF
  > [paths]
  > path0 = https://example.com/path0
  > path1:pushurl = https://example.com/path1
  > EOF
  $ hg paths
  path0 = https://example.com/path0

unknown sub-options aren't displayed

  $ cat > .hg/hgrc << EOF
  > [paths]
  > path0 = https://example.com/path0
  > path0:foo = https://example.com/path1
  > EOF

  $ hg paths
  path0 = https://example.com/path0

:pushurl must be a URL

  $ cat > .hg/hgrc << EOF
  > [paths]
  > default = /path/to/nothing
  > default:pushurl = /not/a/url
  > EOF

  $ hg paths
  (paths.default:pushurl not a URL; ignoring)
  default = /path/to/nothing

#fragment is not allowed in :pushurl

  $ cat > .hg/hgrc << EOF
  > [paths]
  > default = https://example.com/repo
  > invalid = https://example.com/repo
  > invalid:pushurl = https://example.com/repo#branch
  > EOF

  $ hg paths
  ("#fragment" in paths.invalid:pushurl not supported; ignoring)
  default = https://example.com/repo
  invalid = https://example.com/repo
  invalid:pushurl = https://example.com/repo

  $ cd ..

'file:' disables [paths] entries for clone destination

  $ cat >> $HGRCPATH <<EOF
  > [paths]
  > gpath1 = http://hg.example.com
  > EOF

  $ hg clone a gpath1
  abort: cannot create new http repository
  [255]

  $ hg clone a file:gpath1
  updating to branch default
  0 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ cd gpath1
  $ hg -q id
  000000000000

  $ cd ..